:. V. Agriculture and Vegetation. 



SECT. V. 



Of the fandy foil 



THi s foil gets its name from the quan- 

 tity of fand which it contains. The 

 qualities of this foil depend on the qualities 

 of fand. This body differs much from 

 the two former j from the latter, as it eafily 

 admits the entrance of water; from the 

 former, as it does not detain the water like 

 it, which feems to attract moifture with con- 

 fiderable force, and to refift its efcape again ; 

 while fand allows it to pafs eafily through 

 its body, and does not fwell, but, on the 

 contrary, turns lefs in bulk, when wet. 

 Sand cannot detain the water fo long as 

 the rich foils, becaufe it does not contain 

 thofe faponaceous and mucilaginous juices 

 which thefe do, and with which the water 

 is combined and detained. Hence fandy 

 foils often want a fufficient quantity of moi- 

 fture for the nourishment of plants. Hence 

 C 4 they 



